SDSU BIOL 203 EXAM 4 FEUER
QUESTIONS & ANSWERS (GRADED
A+)
What is the difference between heterozygous and homozygous individuals? -
ANSWERAll of the gametes from a homozygote carry the same version of the gene
while those of a heterozygote will differ
When constructing a Punnett square, the symbols on the outside of the boxes
represent _______, while those inside the boxes represent _______. -
ANSWERgametes, progeny
Bacterial artificial chromosome (BAC) - ANSWERA large plasmid that acts as a
bacterial chromosome and can carry inserts of 100,000 to 300,000 base pairs
Complementary DNA (cDNA) library - ANSWERMade by cloning DNA made in vitro
by reverse transcription of all the mRNA produced by a particular cell
True/false: a cDNA library represents the entirety of the genome - ANSWERFalse
DNA does not store the information to synthesize which of the following? -
ANSWEROrganelles
Transcription begins at a promoter. What is a promoter? - ANSWERA site in DNA
that recruits the RNA Polymerase
Which of the following statements best describes the promoter of a protein-coding
gene? - ANSWERThe promoter is a nontranscribed region of a gene.
What determines which base is to be added to an RNA strand during transcription? -
ANSWERBase pairing between the DNA template strand and the RNA nucleotides
Which of the following terms best describes the relationship between the newly
synthesized RNA molecule and the DNA template strand? -
ANSWERComplementary
Nucleic acid hybridization - ANSWERA clone carrying the gene of interest can be
identified with a nucleic acid probe having a sequence complementary to the gene
DNA probe - ANSWERUsed to screen a large number of clones simultaneously for
the gene of interest
, Gel electrophoresis - ANSWERIndirect method of analyzing and comparing
genomes. Molecules are sorted into "bands" by their size
Restriction fragment length polymorphism (RFLP) - ANSWERCan be used to
compare two different DNA molecules such as two alleles for a gene.
True or false? The same phenotype can be produced by more than one genotype. -
ANSWERTrue. Since there exist dominant and recessive versions of many genes, a
phenotype that is based upon the dominant version will be expressed in both
homozygous (AA) and heterozygous (Aa) genotypes
True or false? In diploid organisms, a dominant phenotype will only be expressed if
the individual is homozygous dominant for that trait. - ANSWERFalse. A dominant
phenotype is indeed expressed if the individual is homozygous dominant for that
trait, but the dominant phenotype is also expressed if the individual is heterozygous
for the trait. In fact, heterozygous expression is the definition of dominant
If an organism with the genotype AaBb produces gametes, what proportion of the
gametes would be Bb? - ANSWERNone. Alleles of the same gene must separate
during gamete formation; thus, the two B alleles would be distributed to different
gametes
Two mice are heterozygous for albinism (Aa) . The dominant allele (A) codes for
normal pigmentation, and the recessive allele (a) codes for no pigmentation. What
percentage of their offspring would have an albino phenotype? - ANSWER25. The
offspring would be in a 3:1 ratio of normally pigmented mice to albino mice
A tall, purple-flowered pea plant (TtPp) is allowed to self-pollinate. (The recessive
alleles code for short plants and white flowers.) The phenotypic ratio of the resulting
offspring is 9:3:3:1. What is the genotype of the plant whose phenotype appeared
once out of every 16 offspring (the "1" in the 9:3:3:1 ratio)? - ANSWERttpp. The
smallest phenotypic group consists of the homozygous recessive plants, which in
this case are short and white flowered
Which of the following has had the biggest influence on increased genetic testing in
the United States? - ANSWERMore insurance companies are paying for the tests
our friend discovers that he has the gene for an increased risk of getting early-onset
Alzheimer's disease. The Genetic Information Nondiscrimination Act allows for him to
not face discrimination when he applies for which of the following? - ANSWERHealth
insurance
In which of the following states are you least likely to be discriminated against based
on your genetic profile no matter what type of insurance you need? -
ANSWEROregon
Your employer asks your medical provider for your entire medical record, including
any genetic information. Which of the following is true? - ANSWERFederal law
protects you from having your employer obtain your genetic information.
QUESTIONS & ANSWERS (GRADED
A+)
What is the difference between heterozygous and homozygous individuals? -
ANSWERAll of the gametes from a homozygote carry the same version of the gene
while those of a heterozygote will differ
When constructing a Punnett square, the symbols on the outside of the boxes
represent _______, while those inside the boxes represent _______. -
ANSWERgametes, progeny
Bacterial artificial chromosome (BAC) - ANSWERA large plasmid that acts as a
bacterial chromosome and can carry inserts of 100,000 to 300,000 base pairs
Complementary DNA (cDNA) library - ANSWERMade by cloning DNA made in vitro
by reverse transcription of all the mRNA produced by a particular cell
True/false: a cDNA library represents the entirety of the genome - ANSWERFalse
DNA does not store the information to synthesize which of the following? -
ANSWEROrganelles
Transcription begins at a promoter. What is a promoter? - ANSWERA site in DNA
that recruits the RNA Polymerase
Which of the following statements best describes the promoter of a protein-coding
gene? - ANSWERThe promoter is a nontranscribed region of a gene.
What determines which base is to be added to an RNA strand during transcription? -
ANSWERBase pairing between the DNA template strand and the RNA nucleotides
Which of the following terms best describes the relationship between the newly
synthesized RNA molecule and the DNA template strand? -
ANSWERComplementary
Nucleic acid hybridization - ANSWERA clone carrying the gene of interest can be
identified with a nucleic acid probe having a sequence complementary to the gene
DNA probe - ANSWERUsed to screen a large number of clones simultaneously for
the gene of interest
, Gel electrophoresis - ANSWERIndirect method of analyzing and comparing
genomes. Molecules are sorted into "bands" by their size
Restriction fragment length polymorphism (RFLP) - ANSWERCan be used to
compare two different DNA molecules such as two alleles for a gene.
True or false? The same phenotype can be produced by more than one genotype. -
ANSWERTrue. Since there exist dominant and recessive versions of many genes, a
phenotype that is based upon the dominant version will be expressed in both
homozygous (AA) and heterozygous (Aa) genotypes
True or false? In diploid organisms, a dominant phenotype will only be expressed if
the individual is homozygous dominant for that trait. - ANSWERFalse. A dominant
phenotype is indeed expressed if the individual is homozygous dominant for that
trait, but the dominant phenotype is also expressed if the individual is heterozygous
for the trait. In fact, heterozygous expression is the definition of dominant
If an organism with the genotype AaBb produces gametes, what proportion of the
gametes would be Bb? - ANSWERNone. Alleles of the same gene must separate
during gamete formation; thus, the two B alleles would be distributed to different
gametes
Two mice are heterozygous for albinism (Aa) . The dominant allele (A) codes for
normal pigmentation, and the recessive allele (a) codes for no pigmentation. What
percentage of their offspring would have an albino phenotype? - ANSWER25. The
offspring would be in a 3:1 ratio of normally pigmented mice to albino mice
A tall, purple-flowered pea plant (TtPp) is allowed to self-pollinate. (The recessive
alleles code for short plants and white flowers.) The phenotypic ratio of the resulting
offspring is 9:3:3:1. What is the genotype of the plant whose phenotype appeared
once out of every 16 offspring (the "1" in the 9:3:3:1 ratio)? - ANSWERttpp. The
smallest phenotypic group consists of the homozygous recessive plants, which in
this case are short and white flowered
Which of the following has had the biggest influence on increased genetic testing in
the United States? - ANSWERMore insurance companies are paying for the tests
our friend discovers that he has the gene for an increased risk of getting early-onset
Alzheimer's disease. The Genetic Information Nondiscrimination Act allows for him to
not face discrimination when he applies for which of the following? - ANSWERHealth
insurance
In which of the following states are you least likely to be discriminated against based
on your genetic profile no matter what type of insurance you need? -
ANSWEROregon
Your employer asks your medical provider for your entire medical record, including
any genetic information. Which of the following is true? - ANSWERFederal law
protects you from having your employer obtain your genetic information.
